SAE International The Recent Upgrade of the Model Scale Wind Tunnel of University of Stuttgart 2017-01-1527

After being in operation since 1989, the 25% / 20% model scale wind tunnel of University of Stuttgart received its second major upgrade in 2016. In a first upgrade in 2001, a rolling road with a 5 belt system from MTS was installed. This system includes a steel center belt to simulate the road underneath the vehicle and four FKFS designed rubber belts for wheel rotation. The recent upgrade now enables the wind tunnel to be used not only for standard, steady state aerodynamic measurements but also for measurements of unsteady aerodynamic effects. This enables the use of the FKFS swing system as a standard measurement technique. Therefore, the former balance was replaced by a balance manufactured by AND with a high Eigenfrequency and the ability to sample the measurement data at up to 1000 Hz. The second large part of the upgrade was the replacement of the control system. With the new Wind Tunnel Control System (WCTS), control system. With the new Wind Tunnel Control System (WCTS) supplied by the German companies Werum and SEA, all wind tunnel systems are controlled and operated by a single system. This includes systems are controlled and operated by a single system. This includes the control of the new balance, the rolling road, the fan, the boundary layer control, as well as the traverse system and the pressure measurement system. This paper will give an overview of the newly installed and upgraded systems in the model scale wind tunnel and includes also a summary of the characteristics of the tunnel.